I've done so in the past without issue. Especially when it was 100 percent virtual during the pandemic.
If you have a digital pass you will have the confirmation email/receipt etc. In addition to that maybe take screenshots occasionally and if you want to be really safe some contemporaneous notes. That way in the event of an audit when you write it up you will have some supporting artifacts.
and...maybe email the ISC2 CPE email address to confirm as well. At the end of the day, the RSAC is worth participating in virtually or otherwise even if you don't claim the CPEs.
Also, if I remember correctly, if you have a login/acct for rsaconference.com you can print your viewing history. But would have to double check.
@AndreaMooreCan you provide any insight?